miR-135b-5p通过靶向下调XBP1增强MCF-7/DOXR细胞对阿霉素敏感性的机制  

Mechanisms of miR-135b-5p enhancing the sensitivity of MCF-7/DOXR cells to doxorubicin by down-regulating XBP1

作　　者：毛俊峰[1] 黄向华[1] 卫颖泽[2] 程春[1] 陈橼[1] 吴晓丹[1] MAO Junfeng;HUANG Xianghua;WEI Yingze;CHENG Chun;CHEN Yuan;WU Xiaodan(Department of Surgery,Nantong Cancer Hospital,Nantong 226001,Jiangsu,China;Department of Pathology,Nantong Cancer Hospital,Nantong 226001,Jiangsu,China)

机构地区：[1]南通市肿瘤医院外科,江苏南通226001 [2]南通市肿瘤医院病理科,江苏南通226001

出　　处：《西部医学》2021年第9期1305-1310,共6页Medical Journal of West China

基　　金：国家自然科学基金青年基金(81702634)。

摘　　要：目的探讨miR-135b-5p通过调控X盒结合蛋白(XBP1)对MCF-7/DOXR细胞阿霉素敏感性的机制。方法采用Westernblot检测XBP1的表达水平;RT-qPCR法检测XBP1 mRNA在乳腺癌细胞MCF-7和乳腺癌阿霉素耐药MCF-7/DOXR细胞中的表达水平以及miR-135b-5p的表达水平;CCK-8检测MCF-7/DOXR细胞的增殖情况;Annexin-V-FITC双染流式细胞术检测MCF-7/DOXR细胞的凋亡情况;双荧光素酶报告基因验证miR-135b-5p与XBP1的调控关系。结果XBP1在乳腺癌细胞MCF-7和MCF-7/DOXR细胞中均高表达(P<0.05),敲降XBP1可显著抑制MCF-7/DOXR细胞增殖并促进了细胞凋亡(P<0.05)。双荧光素酶报告基因证实,XBP1是miR-135b-5p的潜在靶基因,miR-135b-5p靶向下调XBP1的表达水平(P<0.05)。实验进一步证实,过表达miR-135b-5p下调XBP1进而显著抑制MCF-7/DOXR细胞增殖并诱导细胞凋亡(P<0.05)。结论miR-135b-5p通过下调XBP1增强MCF-7/DOXR细胞对阿霉素的敏感性。Objective To investigate the mechanism of miR-135b-5p on the sensitivity of MCF-7/DOXR cells to doxorubicin by regulating XBP1.Methods The expression level of XBP1 protein was detected by Western blot.The expression level of XBP1 mRNA in breast cancer cells MCF-7 and breast cancer doxorubicin-resistant MCF-7/DOXR cells and the expression level of miR-135b-5p were detected by RT-qPCR.CCK-8 was applied to measure the proliferation of MCF-7/DOXR cells.Annexin-V-FITC double staining assay was applied to detect the apoptosis MCF-7/DOXR cells.Dual-luciferase reporter assay was used to verify whether XBP1 was a target gene of miR-135b-5p.Results XBP1 was highly expressed in MCF-7breast cancer cells and MCF-7/DOXR cells(P<0.05 or P<0.01).Knockdown of XBP1 significantly inhibited MCF-7/DOXR cell proliferation and promoted apoptosis(P<0.05 or P<0.01).The dual luciferase reporter gene confirmed that XBP1 is a potential targets gene of miR-135b-5p,and miR-135b-5p targets down-regulated the expression level of XBP1(P<0.05).It was further confirmed by recovery experiments that overexpression of miR-135b-5p down-regulated XBP1 and significantly inhibited MCF-7/DOXR cell proliferation and induced apoptosis(P<0.05 or P<0.01).Conclusion miR-135b-5p enhances sensitivity of MCF-7/DOXR cells to doxorubicin by down-regulating XBP1.

关 键 词：乳腺癌 XBP1 miR-135b-5p 阿霉素 敏感性 耐药性 MCF-7/DOXR 

分 类 号：R979.1[医药卫生—药品]